#include <bits/stdc++.h>
using namespace std;

#define int int64_t
#define endl "\n"

using PII = pair<int, int>;
using TII = tuple<int, int, int>;
template<class T>
using V = vector<T>;
using i64 = long long;
using i128 = __int128;
using u64 = unsigned long long;

#define FOR(i, a, b) for (int i = (int)(a); i <= (int)(b); i++)
#define FOR2(i, a, b, c) for (int i = (int)(a); i <= (int)(b); i += c)
#define FORD(i, b, a) for (int i = (int)(a); i >= (int)(b); i--)
#define FORD2(i, b, a, c) for (int i = (int)(a); i >= (int)(b); i -= c)
#define ALL(a) a.begin(), a.end()
#define RALL(a) a.rbegin(), a.rend()
#define lowbit(x) ((x)&(-x))
#define RE return;
#define Yes cout << "Yes" << endl;
#define YES cout << "YES" << endl;
#define No cout << "No" << endl;
#define NO cout << "NO" << endl;
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define sz size()

void solve () {
    int n, m;
    cin >> n >> m;
    V<V<int>>g (n + 1);

    FOR (i, 1, m){
        int a, b;
        cin >> a >> b;
        g[a].eb (b);
        g[b].eb (a);
    }

    V<int>p (n + 1, 0), siz (n + 1, 0);

    FOR (i, 1, n)p[i] = i, siz[i] = 1;

    function<int (int)>find = [&] (int x){
        if (x != p[x])p[x] = find (p[x]);
        return p[x];
        };

    set<int>s;
    V<bool>vis (n + 1, 0);

    FOR (i, 1, n){
        if (i != 1)s.erase (i);
        vis[i] = 1;

        for (auto& j : g[i]){
            if (vis[j]){
                int a = find (i), b = find (j);
                if (a != b){
                    p[a] = b;
                    siz[b] += siz[a];
                }
                continue;
            }
            s.insert (j);
        }

        if (siz[find (i)] != i){
            cout << -1 << endl;
            continue;
        }
        cout << s.sz << endl;
    }

}

signed main () {
    int Task = 1;

    ios::sync_with_stdio (false);
    cin.tie (nullptr);

    while (Task--) {
        solve ();
    }

    return 0;
}